Ophthalmic lens



`A r1 2, 1935. H. HSTYLL A 19969 OPHTHALMI L ENS Filed Jan. 3, 1935 INVENTOR Patented Apr. 2,1935

' .I T A'LMIC LENs l b Harry H. Styll Southbridge Mass., assgnor to 7 American yoptical Company, Southbridge, 7 v Mass-, a voluntary association of Massachusetts Appii'oation Ja ary' 3, 1933,"erial No. 649,956 9 Claims. (Cl. e-54) This invention relates to improvements in l lenses and: has particular `reference tos improved lenses for changing the; size 'of image without change .of focus andto an improved" process for makingthesame v One of the principalobjects ,of theinvention is to provide lenses of this character' of'a reduced size and Weight to facilitate their mounting and use and to provide improved means 'of making them. o

'Other objects and advantages' of the invention will become apparent from the following (iescription' taken in connection with -theaccompanying drawing. Itwill be apparent that many changesmay be made in the details of construcembodying ti Fig: II is a cross section showing one form'of the lens.

` Fig. III is a view similartoFig. II but showin another form of the inVention.; s l

o Fig IVis a View similar ,to Fig.v I I, showingvyet another formof the invention. v A o Fig. v is a view similar to Fg I, showing another form of theinvention. j y i Fig. VI is a front Viewof a modified form of the invention. g

Fig.,VII is a View form of theinvention, and o Fig. VIII is a diagrammatic view in section showing the relation `of the lens to the eye.

Lenses having an optical.` correctionfor. sie

of mage without change of focus have been re v Due to the fact that such' lenses have usually been made inthe form ofa,

cently put in use.`

lens System of separate pieces or lenses they have been very ungainlibfpoor appearancheavy;

and clifilcult to mount before'the eye. Due to the fact that an additional correcton'has been added to those thathave been employed up to the present, difiiculty' Will bev experienced from excessive weight and size', even when the lens is made"in a single piece. It is, thereiore one of the' main Objectsjof my invention to obtain the advantages of such a lens and at the same time reduce the" present difficulties "of s ize, weight, and loosfas hasbeen referred to above. w I

Referring .io the drawing in Which similar reference Characters represent similar parts thoughout: l In Fig. VIII I have shown an elementary lens of 'two parts designed tochangethe sizeof ilri-'- age without change of power, The eye isshown v at 3. The element l is theordinary prescrip tionlens having the surfaces l i and 15' designed:

,in the usual 'prior art 'way' for corrctions ,of

sphere, cylinder and prism, one. a1l,'or any, The element' 2 is the .element'that providesthe change in size of image without change of power.

It has the surfaces I6 'and I"l arranged 'as follows: e The relationship of the surfaces :16 and Il is such as toprovide'no optical powerbut amag-r.

nification. These surfaces may be fiat, sph erical, aspherical, orcylindrical., The amount. of

change in size depends upon the curvatures of the l two surfa'ces'and the thickness .of the element.. Where change in size of the two major meridians is desired, Spherical surfaces' are used; when change in one meridian only is desired, cylindrical surfac'es are used. Such `a 'lens element asis well known produces size changelwithout power change. In such a lens element the two surfaces, in order to produce no optical power, are nearly concentric or substantially equal. The explanation of this is that in the practical range of .ophthalmic lenses'equal Surfaces and` concentric .surraces are 'substantially alike. lens with equal surfacesproducea no-power, but increase of thickness does'produce some power butin the practical range of ophthalmic lenses 35 i V surfacewillcompensate the thickness, as for ex-" it is Very small and a very small alteration of a ample,`a'lens 3' mm. thick having' a 6.00 diopter front surface would have a 6.07 diopterrear sur-,

face for no power, hence, by substantially equal '4 surfaces and nearly concentric' surfaces: is meant herein Surfaces that will produce no power'with the desired thickness.

`When' the concave side i placed nearest the eye the size of image is in-' creased; when the convex side of -the'elementz is. nearest the'eye the size of the imageisdecreased.

of the element i The desired change 'in size is obtained'- by the rethe thickness thereof, by wellunderstood optical lationship of the two surfaces of the element and element is due to the bending or'ourvingof the z element. If an object is Viewed through a plane parallel the effect of this plane 'p'arallelis'negli 'gible.' If, however, we bend'the'plane parallel, as ,happens when'it is ground on' different 'basa y U. s. patent to Von Rohr, N ,'949,501,; Feb 15,

' A IIlFg; V is shown a lens like Fig. II -with the addition ofan additional lens element li' with a separator [2 betweenit and thelens element '4; The parts' may be cemented or used togethrf 'The lenselement li gives additional piece.

" elements. Av

surfaces for"'correc tive .purposes if desired or "needed In some .instancesitmay be made' a prism element. v A In Fig. VI I *have shown the Corrective lens occupying the bottorn part of the device instead 'of the central part as'shown in Fig.I.

In Fig. VII is shown alens similar to l 'ig. VI except that 'the' correction lens is made in one It iclear that the correction lens may be placed in any desired positional, relationship with the The support isshaped to the desired lens shape and may or may' not be formedowith a focal and/or ni'agnification correction as desided and' 7 the edges bevelled to fit a frame or mounting.

' way to simple and good appearing mountings.

' It will be understood that the separate lens elements may be made of glasses of any 'desired indices of refractionand 'that the' said elements maybe secured together byuniting their entire peripheral edges Or by uniting the Said edges'only at afew selectedv spots. This uniting depends largely-upon the shape and curvatures of the From the foregoing it Will b e-seen that I have provided simple,"efiioient and ineXpenSiVe means for obtaining all the advantages of the inventio and for performing its objects.

Having described my invention, I Claim:

1. A lens comprising a lens element having optical surfaces on its two faces of substantially the same curvature, said element having Substantially no optical focal power, a lens element having CurVed optical Surfaces on its two faces, said surfaces being substantially difierent in curvature quired optical properties of the two elements, and

a filler piece of optical glass filling the marginal.

.space between the elements but not the central portion thereof, and a third lens element having optical surfaces on its faces aligned with the other two elements and spaced from one of them and a filler piece between said last two elements.

2. A lens comprising a lens element having optical surfaces on its two faces of substantially the same curvature, said element having substantially no optical focal power, a lens element having curved optical surfaces on its two faces, said surfaces being substantially different in curvature and having focal power, said two elements being aligned one With the Other with their adjacent Surfaces separated by a distance to givethe required optical properties of the twoelements, and a, filler piece of optical glass filling the marginal space between the `elements but not the central portion there o f, said filler piece being -extended beyond the margin of the edges of said two elements, and a third lens elementhaving optical surfaces on its aces aligned With'the Other two elements and spaced from one of them and a filler piece betweensaid last two elements, said filler piece beingn'ot extended beyond the Inargins of theflens elements.

3. A lens comprising a lens system having o p-' 'posed concavo-convex optical surfaces upon its faces, the algebraic sum of said surfacesbeing equal optically to a lens system comprising two superimposed lensunits, One in front :of the other, one of-said units having optical surfaces on its' being substantially different to produce arequired focal power and a carrier piece of optical'glass extending outwardly from themarginal -edges of said system, the peripheral contour of "said carrier piece in size and shape being thatjof an ordinary prescription ophthalmic lens, andthe lens system portion thereof being' spaced inter-.

nally of the marginal edges of the carrier piece and occupying Only a fractional'part of the ex tent of the whole lens.

- 4. A lens comprising an optical power portion and a non-lenticular supporting portion, the size and contour of the supportingpor-tion being that of an ordinary' p'rescription ophthalmic lens'and the power'portion spaced internally of the-mar l ginal edges of the' supporting portion and'occupying only a fractional part of the'extent of the whole lens, Said' power portion projecting beyond the surfaoe of the supporting portion on each side y faces, the algebraic sum of'which is equal optically-"to a lens systemcomprising two superimof said units having optical surfaces on its two faces of substantially the same curvature' and deflected from a fiat plane by an amount'to give a. y required magnification and having substantially no optical power and the other unit having curved posed lens units, -one in front of the other, one

optical surfaces on its two faces, said surfaces being substantially different to produce a required focal power.

5. A` lens comprising two field portions, one b of said portions being of the peripheral size and contour of ordinary prescription ophthalrni o lenses and' the other of said portions occupying only a portion of the extent of the first p'ortion and having optical surfaces on its opposed faces, said opposed surfaces being concavo-convexoi required focal power having an algebraic sum equal optically to a lens system comprising two superimposed lens units, one in front of the other, one of Said units having optical surfaces on its two faces of substantially the same curva ture and deflected from a fiat plane by ""an amount to give a required magnifi'cation and having substantially no optical power and the other unit having curved optical surfaces on its "two faces, said surfaces being substantially different to produce arequired focal power. p

6. A lens comprising two field portions, one of said portions being of the peripheral size and contour of o rdinary prescription ophthalmic lenSeS" and the other of said portions oooupying only a portion of the extent of the first portion and comprising a plurality" of vlens 'units supported by plane by an amount to" introduce a required maniflcatiom and. another of. said units having optical opposed concavoy-convex Surfaces on its faces, Said surfaces having asubstantial dier ence .in' cuivature from each'other; said di fier ence being an 'amount to produce`a`, 1 "equred focal power, the algebraic sum of'all of said s urfaces'being equal to'the required focal power but sad:units having athikness and a bending 'awayfroma fiat plane difierent from the bend-` ing ofa lens of said requirediocal 'power'having focal power alone whereby is included' the required magnification in said second portion.

. ;7-. "A"1ens comprising two field portions, one of'sad portions being of the perpheral size and only a portion of the extent of ,therst portion i A and compris'ing -a plurality 'of lens units 'supp'ortedby the said first portiom one'of ,Said `.units "having optical, opposed' concavo-convex contour of, 'ordinary :prescription 'ophthalmic lenses and the other of said'portions occupying surf aces on its faces, said -surfaces being 'of substantially the same curvature and cley flected 'away from a flat plane by an amounti to introduce a required magnification and another of; ,said units having -optical opposed coneavoconvex 'surfaces on its faces, said surfaces having ia substantial differencein urvaturefrom each other, Said difierence'being an ,amount to prooptical sur faees aligned with said second portion, 8. A lens comprising two fie1ds, one fieldjex- 1,99o,o8 o' i i n tending beyond'theed ge or the other." oneof said fields being a'field for supporting 'the .otherand havingflnished optical surfaces 'of' desired .optical power on its two"faces,` thes upported field, being' a lens systemoptically 'equivalent fto t two superimposedlens units, one in front of the other'. wherein one ofsaid units has opticaLsuraeson its two facesof substantially :the same' 'curyatu and has substantially no optieal` :focal power and i being defleeted troni 'a'fiat plane by; an amount. to produce a requiredjmagniflcation; 'and the other unit has, -curved 'optical surfaces'onits two faces; said surfacesbeing substantially qif? V V ferent in curvature to an amountto produce a requiredfocal power, the defiection'o'the len 'units away from a flat plane being 'different from the same opticalpowerwithout magnification.

fields being a field for 'supporting the .other and one of said fields being a lens systein optically equiyalent to two separate ali gnedlens units, one' in front of the other whexeinfque' of 'Said units' has optical surfaces on" its two races psubstan no optical 'focal power and being defieqted irom' a flat 'plane by: an amount to produce ajrequired magnifieatio and the other unit avingfcurved optical surfa'ces on its two races, saidsurface being. substantially 'different in curvature by an amountto'produce a' requiredfocal po v ven 'the i i being different fromwhe deflection from-a =flat 't plane of a lens ofthe same optical power with,-

out magnification. l A

, u `y ARRYH.sTYLL. 

